Parishioners at the Stornoway High Church on the Isle of Lewis in Scotland still remember the dignified blonde who came back from America every summer. She walked with a formal, erect posture, provoking whispers about how she’d picked up her “airs and graces” in New York, where she’d married a rich man. But mostly they remember her speaking Gaelic as though she’d never left the island.

The woman, Mary Anne MacLeod, is the mother of Donald Trump, the aggressive rich kid turned real estate mogul turned President of the United States. And the contrast between her humble immigrants roots and the 1950s McMansion where she wound up is the key to understanding Trump’s deep insecurity.

MacLeod spent the first 17 years of her life in Tong, a fishing village on the Isle of Lewis, in the Outer Hebrides, closer to Iceland than to London. Though her son was raised in a mansion in Queens, she grew up among poor islanders in a two-bedroom rented cottage crammed with her and 10 siblings.

The MacLeods lived several miles from their church, on a tidal flat the locals called “the saltings.” At certain times of day, the muck turned into quicksand as the tide rose. To get to church on Sunday—a daylong affair—the family would pick their way across the flats in muck boots—a perilous journey that only fishing families would even attempt because people frequently drowned. On every other day of the week, MacLeod’s family worked hard, digging peat to burn, hauling fishing nets in the icy rain and farming meager crops they grew in the rocky soil.

Donald Trump's mother, Mary McCloud, at home in Stornoway in Scotland. Mirrorpix

As a girl, MacLeod saw few examples of how rich people lived. An English opium baron named Matheson had purchased the entire island in the mid-19th century and built himself a turreted gray stone Victorian castle on a plot of land overlooking Stornoway. The family’s church was on Matheson Road, a street lined with small but handsome brick mansions belonging to the families of local merchants. To distinguish themselves from their impoverished—and often fish-smelling—counterparts, residents of these mansions forbade the poor to walk on their street. That ban would have included MacLeod and her family, local residents say.

Poor islanders had been abused by the wealthy for years. In her grandparents generation, the British had expelled tens of thousands of Scottish peasants in order to empty the land for sport hunting and sheep. Thousands emigrated to North America, climbing on ships whose conditions were so bad that many perished of scurvy and other ailments before they reached land. Those left behind clung to the traditional ways—farming, fishing and speaking Gaelic at church and school—even as their English overlords tried to force their language upon them. MacLeod, for instance, did not hear much English until she enrolled in school, which was compulsory only until 8th grade.

Another crisis also pushed MacLeod’s generation to leave. She was only seven when World War I ended, but the conflict and a local maritime disaster, a winter shipwreck just yards from shore, killed 200 soldiers returning from the front, decimating the male population. That shortage of men, and the promise of a better life in America, prompted her to join her older sisters in New York in 1929. (They were married to butlers and working as maids or servants, and secured her a job when she arrived.) According to a local genealogist, all the MacLeod siblings eventually emigrated to North America, except one who remained behind and took care of the parents.

The exodus from Lewis was so dramatic in MacLeod’s generation, that the same month the 17-year-old sailed away on a steamer for New York, her local paper, the Stornoway Gazette editorialized: “Our straths and glens will soon be peopled only with middle-aged and elderly people. Most of these young people take kindly to the life of those distant lands but they never forget the ‘old folk at home.’”

The men they left behind, fed up with aristocratic landowners, staged a series of raids to seize what British authorities had promised them if they fought in World War I—their own land. Landowners gave in and granted back property to the tenant farmers in the community. Modern day island families living on this land pay rent to a public trust, not English lords.

Six years after she arrived in New York, MacLeod, the blue-eyed youngest member of her family, met a blonde, mustachioed, first-generation German-American at a party in Queens. They later married.

Fred Trump was a nobody back then, but he soon became one of the biggest home builders in suburban New York. His wife spent her adult years recreating the pomp she’d viewed from the proverbial window as a girl. Despite her lack of education and lowly roots, she liked to wear furs and be chauffeured in a Rolls Royce around plebeian Queens, New York. In his book, Trump: Art of the Deal, the New York real estate mogul wrote about her passion for the trappings of wealth. She was so enthralled by the coronation of Queen Elizabeth that her no-nonsense German-American husband begged her to turn off the TV.

Her son Donald inherited her obsession with the trappings of class and luxury—and his own insecurity about not being to the manner born. He built himself a miniature Versailles, his gold and marble triplex in Trump Tower—designed by another immigrant with queenly tastes, first wife Ivana Trump. And perhaps because his mother left Scotland with less than a high school education, he has sneered at people with academic degrees. “The most important thing I learned at Wharton was not to be overly impressed by academic credentials,” Trump wrote in The Art of the Deal. “It didn’t take me long to realize that there was nothing particularly awesome or exceptional about my classmates, and that I could compete with them just fine.” In the same book, he thumbed his nose at old money New Yorkers who didn’t like his buildings and has said he worries Ivanka “looks down on him.”

But while MacLeod had airs and graces, she never turned her back on her roots. On the contrary, she always returned to Tong, year after year, lapsing into Gaelic the minute she arrived. The islanders cite the Gaelic saying “The bird sings best in its nest” to explain her attachment. Trump, though, never came with her.

Today, the peat fields are still part of the island’s landscape, but residents are more connected to the rest of the world. Hundreds of cruise ships dock at Lewis in the summer. But the spirit of the island, population 18,500, remains community oriented: Neighbors pitch in when a family is in trouble, and they rarely lock their doors.

The people of Lewis were amused and proud of their American son, Donald, when they first learned he was a reality-TV celebrity. But after he strong-armed mainland Scots near Aberdeen into land concessions for his “best golf course in the world,” and as his political career swerved into scandal, many in his mother’s hometown grew ashamed of him. A Facebook page called Isle of Lewis Against Trump is decorated with a photograph of a Trump troll doll. “He is not proud of his mother’s humble beginnings,” said the novelist and poet Kevin MacNeil, who lives on the Isle of Lewis. “It is hard to understand how in a single generation the values of altruism, togetherness and sheer human decency were lost. Selflessness became selfishness. A supportive sense of community became a vain-glorious arrogance.”

Trump has claimed his mother came to America on a holiday and decided to stay in the big city, a story which causes islanders roll their eyes. It’s not clear whether MacLeod told her family this fib or whether it’s just another Trumpian alternative fact—like his claim that his German-American father was actually Swedish.

Trump’s older sister used to accompany their mother to Lewis, but Donald visited Tong only once while he was in Scotland while inspecting work on his golf course in 2008. Scottish journalists clocked his time on the island at 180 minutes, with just 97 seconds at the MacLeod cottage. “I feel Scottish,” he proclaimed on the tarmac, his blonde pompadour wafting vertical in the island breeze.

Beyond that slogan and his golf course, Trump seems to have little use for his mother’s humble roots. His living relatives—second cousins mostly—have stopped talking to journalists since his election. But during the campaign, one of Trump’s cousins, Mairi Sterland, told a Hebridean blogger: “I used to laugh about [being related to] Donald Trump. Now I hardly dare mention him. I’m intrigued that people will even countenance the thought that he might be president. He’s a rabble raiser. He knows how to do it. He’s in that Apprentice thing and he works it. He is outrageous. You quail at the thought of what he’s capable of.”

What would MacLeod make of her famous son now, the blogger asked? “I think his mother would be horrified,” the relative said.